This invention relates to a novel pyrimidine compound and a liquid crystal composition containing the same.
Liquid crystal substances and their compositions have been used in various display devices by utilizing the dielectric anisotropy value (abbreviated to .DELTA..epsilon.) and the optical anisotropy value (abbreviated to .DELTA.n) thereof in their liquid crystal phases, and their display modes are classified as various types, e.g., TN type (twisted nematic type), DS type (dynamic scattering type), guesthost type, DAP type, etc.
However, for liquid crystal materials used for these display elements there is no single substance which per se may be used to obtain all of the various characteristics such as mesomorphic range, operation voltage, response properties, etc.; thus practically, several kinds of liquid crystal compounds have been mixed together or have been mixed with several kinds of non-liquid crystal compounds to obtain materials which can achieve practical use.
In general, a liquid crystal material having an optional .DELTA..epsilon. value is obtained by adequately blending those having different .DELTA..epsilon. values. In order to obtain a liquid crystal composition having a large .DELTA..epsilon. value, it is necessary to use a component having as large a .DELTA..epsilon. value as possible, and in this case, such a component is preferred to have a good compatability with other components and also to lower the viscosity of the resulting composition. Further, the liquid crystal material is required to be stable to moisture, light, heat, air, etc. At present, however, there is no single compound which satisfies all of the conditions, but several kinds of liquid crystal compounds have been blended with each other or with compounds similar to liquid crystals, for practical use.